ALLL Activity (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Allowance for loan and lease losses
Financing Receivable, Allowance for Credit Losses, Beginning Balance	$ 129,054	$ 131,564	$ 131,239	$ 129,568
Provision for loan losses	0	3,194	57	8,707
Charge-offs	(5,890)	(4,294)	(12,090)	(11,905)
Recoveries	2,371	2,071	6,329	6,165
Financing Receivable, Allowance for Credit Losses, Ending Balance	125,535	132,535	125,535	132,535
Residential Real Estate \| Residential Real Estate
Allowance for loan and lease losses
Financing Receivable, Allowance for Credit Losses, Beginning Balance	10,695	10,903	10,631	10,798
Provision for loan losses	(325)	54	(152)	135
Charge-offs	(141)	(210)	(482)	(257)
Recoveries	8	7	240	78
Financing Receivable, Allowance for Credit Losses, Ending Balance	10,237	10,754	10,237	10,754
Commercial \| Commercial Real Estate
Allowance for loan and lease losses
Financing Receivable, Allowance for Credit Losses, Beginning Balance	72,447	71,245	72,448	68,515
Provision for loan losses	(1,480)	2,922	(1,824)	5,941
Charge-offs	(1,858)	(909)	(2,267)	(2,132)
Recoveries	549	308	1,301	1,242
Financing Receivable, Allowance for Credit Losses, Ending Balance	69,658	73,566	69,658	73,566
Commercial \| Other Commercial
Allowance for loan and lease losses
Financing Receivable, Allowance for Credit Losses, Beginning Balance	36,259	38,664	38,160	39,303
Provision for loan losses	1,220	(257)	(524)	415
Charge-offs	(1,399)	(897)	(2,597)	(3,325)
Recoveries	778	447	1,819	1,564
Financing Receivable, Allowance for Credit Losses, Ending Balance	36,858	37,957	36,858	37,957
Consumer and Other \| Home Equity
Allowance for loan and lease losses
Financing Receivable, Allowance for Credit Losses, Beginning Balance	5,801	6,092	5,811	6,204
Provision for loan losses	(777)	(165)	(786)	(359)
Charge-offs	0	(82)	(28)	(101)
Recoveries	17	83	44	184
Financing Receivable, Allowance for Credit Losses, Ending Balance	5,041	5,928	5,041	5,928
Consumer and Other \| Other Consumer
Allowance for loan and lease losses
Financing Receivable, Allowance for Credit Losses, Beginning Balance	3,852	4,660	4,189	4,748
Provision for loan losses	1,362	640	3,343	2,575
Charge-offs	(2,492)	(2,196)	(6,716)	(6,090)
Recoveries	1,019	1,226	2,925	3,097
Financing Receivable, Allowance for Credit Losses, Ending Balance	$ 3,741	$ 4,330	$ 3,741	$ 4,330

A valuation allowance for financing receivables that are expected to be uncollectible.

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- Definition

Amount of recovery of financing receivables doubtful of collection that were previously charged off.

+ References

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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- Definition

Amount of direct write-downs of financing receivables charged against the allowance.

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- Definition

Amount of expense related loan transactions, lease transactions, credit loss from transactions other than loan and lease transactions, and other loss based on assessment of uncollectability from the counterparty to reduce the account to their net realizable value.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (c)(2)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953423-111524

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 220
-Section S99
-Paragraph 1
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-URI http://asc.fasb.org/extlink&oid=114873765&loc=SL114874048-224260

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3602-108585

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